restructuring, some species will thrive. Many plants may in fact benefit
from high carbon dioxide levels, since it will be easier for them to obtain
the CO 2 they need for photosynthesis. Others will fall behind and
eventually drop out.
Silman sees himself as an upbeat person. This is—or at least was—
reflected in his research. “My lab has kind of been the sunshine lab,” he
told me. He has argued publicly that with better policing and well-placed
reserves, many threats to biodiversity—illegal logging, mining, ranching—
could be minimized.
“Even in tropical areas, we know how to stop this stuff,” he said.
“We’re getting better governance.”
But in a rapidly warming world, the whole idea of a well-placed
reserve becomes, if not exactly moot, then certainly a lot more
problematic. In contrast to, say, a logging crew, climate change cannot be
forced to respect a border. It will alter the conditions of life in Manú just
as surely as it will alter them in Cuzco or Lima. And with so many species
on the move, a reserve that’s fixed in place is no stay against loss.
“This is a qualitatively different set of stresses that we are putting on
species,” Silman told me. “In other kinds of human disturbances there
were always spatial refuges. Climate affects everything.” Like ocean
acidification, it is a global phenomenon, or, to borrow from Cuvier, a
“revolution on the surface of the earth.”
THAT afternoon, we emerged onto a dirt road. Silman had collected
various plants that interested him to take back to his lab, and these were
strapped to his enormous backpack, so that he resembled a cloud-forest
Johnny Appleseed. The sun was out, but it had recently rained, and
clusters of black and red and blue butterflies hovered over the puddles.
Occasionally, a truck rumbled by, loaded down with logs. The butterflies
couldn’t scatter fast enough, so the road was littered with severed wings.
We walked until we reached a clutch of tourist lodges. The area we’d
entered, Silman told me, was famous among birders, and just trudging